Poles and similar devices such as masts are used for many functions. Poles are elongated members which are vertically positioned, or otherwise mounted for the purpose of elevating some device or member mounted to the pole. Common examples of poles are flag poles, telephone poles, antenna masts, and sailboat masts. Poles and masts are common examples of elongated support structures, although there are other similar elongated support structures.
Poles and masts are used to support various devices. These devices may be flags, wires, transformers, antennae, irrigation or similar liquid distribution equipment, hoists, or any other article which is elevated.
In the case of many forms of masts or poles, halyards are used to raise and lower articles. In the case of flags and sails, halyards work adequately to raise and lower the articles which are affixed to the flag pole or mast.
Other articles which are supported by poles or masts are more permanently affixed to the pole or mast. For example, a transformer on a telephone pole must be solidly affixed, and not subject to wind and other weather conditions. Accordingly, a halyard would not adequately position a transformer on a pole. Irrigation equipment commonly uses rotating spray nozzles, and such equipment must be affixed to the pole to accommodate the dynamics of the equipment.
Most poles and masts must be rigidly affixed to their support, or to the ground. A tall pole having a working device at the top thereof potentially creates a great moment about the base of the mast. As the pole increases in length, the greater the requirement for support at the base of the pole.
At the same time, it is desirable to easily access the object device which is affixed to the pole. If a rotating spray nozzle needs repair or replacement, access must be available to the spray nozzle. Either the pole must be taken down or a worker must be lifted to the top of the pole. While devices such as cherry pickers can lift a worker to the top of a pole, these devices are expensive.
Alternatively, means may be provided for a worker to climb or otherwise be hoisted to the top of the mast or pole. Such an arrangement increases the need for structural stability of the pole, and presents a substantial safety hazard to the worker.
Masts and poles which are affixed to the ground are normally buried, and are frequently set in concrete. When the pole is secured by setting the pole in concrete, lowering the pole for repair to the pole or the object device that is mounted on the pole presents a major operation.
Ideally, a pole or mast is securely mounted by burying the base of the pole and setting it in concrete, while providing a convenient mechanism for raising and lowering the pole or mast as desired.